The invention relates to the area of protein kinases. More particularly, the invention relates to cyclin-dependent protein kinases.
The pathways responsible for regulating mitosis and migration and for transducing environmental stress signals in cells have not been fully described. Such proteins can be manipulated, for example, to protect cells against stress due to disease or environmental conditions and to treat disorders involving alterations in mitosis or migration, such as neoplasia. Thus, there is a need in the art for the identification of proteins which are involved in these pathways.
It is an object of the invention to provide methods and reagents for diagnosing and treating neoplasia, as well as regulating the cell cycle. These and other objects of the invention are provided by one or more of the embodiments described below.
One embodiment of the invention is an isolated protein comprising an amino acid sequence which is at least 94% identical to the amino acid sequence shown in SEQ ID NO:2. Percent identity is determined using a Smith-Waterman homology search algorithm using an affine gap search with a gap open penalty of 12 and a gap extension penalty of 1.
Another embodiment of the invention is an isolated polypeptide comprising at least 218 contiguous amino acids selected from the amino acid sequence shown in SEQ ID NO:2.
Still another embodiment of the invention is a fusion protein comprising a first protein segment and a second protein segment fused to each other by means of a peptide bond. The first protein segment consists of at least 218 contiguous amino acids selected from the amino acid sequence shown in SEQ ID NO:2.
Yet another embodiment of the invention is a cDNA molecule which encodes a protein comprising an amino acid sequence which is at least 94% identical to the amino acid sequence shown in SEQ ID NO:2. Percent identity is determined using a Smith-Waterman homology search algorithm using an affine gap search with a gap open penalty of 12 and a gap extension penalty of 1.
Even another embodiment of the invention is a cDNA molecule which encodes at least 218 contiguous amino acids of SEQ ID NO:2.
A further embodiment of the invention is a cDNA molecule which is at least 85% identical to the nucleotide sequence shown in SEQ ID NO:1. Percent identity is determined using a Smith-Waterman homology search algorithm using an affine gap search with a gap open penalty of 12 and a gap extension penalty of 1.
Another embodiment of the invention is an isolated and purified subgenomic polynucleotide comprising a nucleotide sequence which hybridizes to SEQ ID NO:1 after washing with 0.2xc3x97SSC at 65xc2x0 C. The nucleotide sequence encodes an hPFTAIRE protein having the amino acid sequence of SEQ ID NO:2.
Still another embodiment of the invention is a construct comprising a promoter and a polynucleotide segment encoding at least 218 contiguous amino acids of an hPFTAIRE protein as shown in SEQ ID NO:2. The polynucleotide segment is located downstream from the promoter. Transcription of the polynucleotide segment initiates at the promoter.
Even another embodiment of the invention is a host cell comprising a construct which comprises a promoter and a polynucleotide segment encoding at least 218 contiguous amino acids of an hPFTAIRE protein as shown in SEQ ID NO:2.
Yet another embodiment of the invention is a homologously recombinant cell having incorporated therein a new transcription initiation unit. The new transcription initiation unit comprises (a) an exogenous regulatory sequence, (b) an exogenous exon, and (c) a splice donor site. The new transcription initiation unit is located upstream of a coding sequence of an hPFTAIRE gene. The hPFTAIRE gene comprises the coding sequence shown in SEQ ID NO:1. The exogenous regulatory sequence directs transcription of the coding sequence of the hPFTAIRE gene.
A further embodiment of the invention is a polynucleotide probe comprising at least 12 contiguous nucleotides of SEQ ID NO:1.
Another embodiment of the invention is a method of detecting migrating cells in a body sample of a human. The body sample is assayed for the presence of an expression product of a gene comprising the coding sequence shown in SEQ ID NO:1. The presence of the expression product indicates that the body sample comprises migrating cells.
Still another embodiment of the invention is a method of diagnosing or prognosing neoplasia. Expression of a first hPFTAIRE gene in a first tissue suspected of being neoplastic is compared with expression of a second hPFTAIRE gene in a second tissue which is normal. The second hPFTAIRE gene comprises the coding sequence shown in SEQ ID NO:1. Over-expression of the first hPFTAIRE gene relative to the second hPFTAIRE gene indicates neoplasia in the first tissue.
Even another embodiment of the invention is a method of identifying an agent which alters mitosis. A cell is contacted with a test compound. Expression of an hPFTAIRE gene is measured. The hPFTAIRE gene comprises the coding sequence shown in SEQ ID NO:1. A test compound which increases expression of the hPFTAIRE gene is identified as a potential agent for inducing mitosis, and a test compound which decreases expression of the hPFTAIRE gene is identified as a potential agent for decreasing mitosis.
The present invention thus provides the art with the amino acid sequence and DNA coding sequence of hPFTAIRE, a unique member of the cyclin-dependent kinase family. The invention can be used, inter alia, to treat neoplasia and other proliferative diseases and to detect the presence of migrating cells.